i have a sawtooth G4 that came with a 450MHz chip, but is getting a bit slow. i didnt feel like spending $300 on a CPU upgrade and i am somewhat of a novice modder so i decided to go pick up a DP G4 500 on craigslist. this one has a fried PSU, and i know i could just stick the psu from the 450 in there but instead i decided to fit the dual 500 into the single 450 case, since all my stuff is already in there. the first time i tried to boot with the new cpu installed, it gave me a bong then lost power before giving signal to the display. i booted it again with the new DP 500 but the same thing happened, so i figured maybe i needed new thermal paste since i took the heatsink off of the cpus during the switch, and this helped me get to the apple logo during the boot process, but then a sort of black curtain rolls over the logo and the whole computer loses power. after a few more tries, i somehow get it to fully boot! i know this is a problem with the cpu, because upon putting the old 450 back in, it works fine... but anyway, after finally managing to boot the dual 500 after numerous kernel panics, i *attempted* to open activity moniter, and then the whole thing completely freezes. after a few more tries and a reset to the pram, i boot it again, and it works fine, that is until i try to do anything taking a lot of cpu cycles, like playing a youtube video that froze it again. hmm, beginning to see a pattern here? it seems when the cpu gets stressed, it freezes... im thinking that somehow the cpu is not getting enough voltage? but im not sure so im asking you guys if you can help? thanks.